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Using builtin list as argument to map #10298

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@PhilReinhold

Description

@PhilReinhold

Bug Report

Mypy emits a spurious error when using the python builtin list as the first argument to the python builtin map

To Reproduce

from typing import List

x: List[str] = list(map(str, range(5)))  # works
y: List[List[str]] = list(map(list, x))  # fails
z: List[str] = list("1")  # works

Expected Behavior

I would expect no error. The builtin in list should satisfy the expected type Callable[[str], List[_T]].

(Write what you thought would happen.)

Actual Behavior

running mypy on this yields error: Argument 1 to "map" has incompatible type "Type[List[Any]]"; expected "Callable[[str], List[_T]]"

Your Environment

  • Mypy version used: 0.812
  • Mypy command-line flags: None
  • Mypy configuration options from mypy.ini (and other config files): None
  • Python version used: 3.7.10
  • Operating system and version: Windows 10

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